Sierra 18-9400CAT-2 25W40 FC-W 4-Stroke Marine Engine Oil Quart

Sierra 18-9400CAT-2 is a premium NMMA FC-W certified catalyst-compatible marine engine oil specifically formulated for modern four-stroke stern drive and inboard engines. This 25W40 viscosity oil provides superior protection for recreational marine engines operating in extreme conditions, whether equipped with emission catalyst systems or not.

Key Features:

• Industry-leading wear protection and deposit control for maximum engine longevity
• Minimizes internal engine corrosion in harsh marine environments
• Enhanced detergent and dispersant properties suspend contaminants and prevent engine sludge formation
• Reduces engine friction for improved efficiency and performance
• High-quality base stocks resist thermal and oxidative breakdown
• Highly shear-stable viscosity stabilizers prevent excessive oil thinning under high stress
• Advanced thermally stable ZDDP anti-wear additive technology prevents phosphorus depletion and extends catalyst life

This FC-W certified formula meets the unique requirements of marine engines that experience frequent idle time, rapid acceleration, and varying load conditions. Each quart bottle provides convenient oil changes for small engines or easy top-offs for larger powerplants.